MDCAT Biology MCQ #284

A baker notices dough rising due to gas production by yeast in the absence of oxygen. What is the chemical nature of this gas?

MDCAT Biology MCQ #284

  1. Question 1

    Q1. A baker notices dough rising due to gas production by yeast in the absence of oxygen. What is the chemical nature of this gas?

    • A) Oxygen
    • B) Lactic acid
    • C) Carbon monoxide
    • D) Carbon dioxide

    Answer: Carbon dioxide

    Explanation: Yeast produces ethanol and CO2 during anaerobic respiration; lactic acid is tempting as it is an animal anaerobic product.